Vibrating screen



Nov. 1, 1938. E. E. DEISTER ET AL VI BRATING SCREEN Filed June 6, 1955 2 Sheets-Sheet l Emil Ei -Deis ie r.

Irwin FIJEiSiEI'Z.

Patented Nov. 1, 1938 UNITED STATES VIBRATING SCREEN Emil E. Deister and Irwin F, Deister, Fort Wayne, Ind., assignors ,to Deister Machine 00., Fort Wayne, Ind.

Application June 6, 1935, Serial No, 25,264

8 Claims, (01. 2091382,)

This invention relates to vibrating screens, and more particularly to an auxiliary vibratory mechanism for imparting a sharp tapping or striking action to the screening medium.

The invention has primarily for its object to provide a novel form of auxiliary mechanism, which overcomes certain limitations found in other mechanism of the character such as that disclosed in pending application Serial No. 063, now Patent. Number 2,032,032, ssued Feb uary 25, 1936, filed February 16, 1933, in that the present invention is capable of use regardless of the condition of material to be handled.

For example, the structure covered by said patent has proved highly successful for handling material under normal conditions but in instances where the material is heated prior to delivery to the screen, as in drying, it has been found that the use of rubber mountings for the striker are objectionable, in that heat radiated from the material is usually of such temperature as to act as a curing medium for the rubber, causing its rapid deterioration and ineffectiveness.

Therefore, a more specific object of the invention is to overcome the foregoing objections by'the provision of an auxiliary tapping or striking mechanism, in which the use of rubber is entirely eliminated, and yet the action of the striker is controlled to a high degree of accuracy for materials of varying characteristics, and also in desired relation to the primary vibrating movement of the screening medium.

A further object of the invention resides in the provision of a tapping mechanism carried by the main frame and supported upon a leaf spring having controlled action induced by the primary vibrating action of the screening medium, and which may or may not utilize auxiliary springs for affecting the action of the leafspring, de-

pending upon the vibratory movement -of the screening medium, and in which means is provided for imparting impact to the screening medium either in an upward, or downward direction, or both.

With the above and other objects in View, which will appear as the description proceeds, the invention resides in the novel construction, combination, and arrangement of parts, substantially as hereinafter described and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the herein disclosed invention may be made as come within the-scope of the claims.

In the accompanying drawings is illustrated one complete example of the physical embodi- 112511? of the present invention constructed according to the best mode so far devisedfor the practical application of the principles thereof.

Figure 1 is a transverse section through a conventionaltype of vibrating screen equipped with I i an auxiliary tapping mechanism designed in accordance with one form of the present invention. Figure 2 is an enlarged plan detail of the spring mounting for the striker, the same being taken on the vibratoryscreen S is supported, the channels 1;.

I being anchored to any suitable foundation formed to position the base at an angle as is customary in screens of this type. Secured upon the channels I are the journalhousings 2, each of which comprises a casing 3 bolted or otherwise attached to the channel, and having an open inner face, which is closed by a resilient disc, 4,

- clamped to the casing 3 by a ring 5 secured to the peripheral flange 6 of the casing. Positioned within each of the housings 2 is a resilient block 1, having journaled therein the ends of a transverse shaft 8, which is engaged by the resilient discs 4 to prevent the entrance of water and dirt into the housings 2'. The foregoing is conventional and illustrated in said Patent No. 2,032,082 Therefore, the same forms no part of the present invention, except insofar as some form of resilient mounting must be employed by the vibrating screen S.

Supported upon the transverse shafts B is a main vibrating frame 9, comprising longitudinal side plates l0, welded or otherwise secured to'the shaft 8, and beingsuita-bly connected at their upper edges by transverse angle braces l l, and the customary end plates (not shown).

In some instances primary vibrating movement is imparted to the screen S by means of a motor mounted upon two of the transverse braces ll positioned at any desired point upon the frame 9 intermediate its ends, the motor shafts being provided with overbalanced fly wheels. However, inasmuch as the present invention is primarily designed for handling material at such temperatures as might affect the windings of a motor mounted directly above the screen, in the present instance the motor is removed,and a, transverse shaft 14 is journaled in bearings l2 carriedby the cross braces H.

Mounted on the shaft I4 are the overbalanced fly wheels i3, which are relatively adjustable to screen frame l9 thereon.

control the vibrating action of themain screen, as fully set forth in Letters Patent No. 1,685,941. Drive is imparted to the shaft i4'by a pulley l5 secured thereto and connected with any suitable source of power (not shown). However, it

is to be understood that vibratory movement may be imparted to the screen S in numerous ways without departing from the invention.

Secured longitudinally to the inner faces of the side plates I0 are angle irons I1, which support the removable screen panels, designated generally as l8, and comprising an outer frame !9 consisting of angle irons secured together at their opposite ends by the usual transverse members, as shown in said Patent No. 2,032,082. Secured on the frame I9 is a screening medium 29, preferably formed from wire mesh, although perforated sheets may be employed in some cases. 7

In assembling the screen panel, desired tension is placed upon the screen 20, and the same is then clamped to the frame H! by longitudinal strips 2 I. Secured to the angle irons of the frame 19 are suitably'spaced blocks 22, which. engage the longitudinal tracks I1,- and support the The frame is then locked in assembled position by means of longitudinal straps 23, engaging both the strips'2l and the'inner faces of the side plates ID. The straps 23 are drawn into clamping engagement with the screen panel and main frame by angularly disposed bolts 24 passing through the side plates Ill and locked to the angle brackets Secured to the bottom surface of the screening medium 20 are a plurality of longitudinal channels 26, which constitute auxiliary vibratory members, in that the same are clamped to the screeningmediuin by straps 21; mounted upon the upper face of the screening medium, and

attached to the channels by bolts 28. Inasmuch as it is desirable to permit vibratory movement of the channels 26, independent of movement of the screen frame IS, the ends of the channels 26 have welded thereto split journal boxes 29, as best shown in Figure 3, which are provided with transverse bearings 30 in the form of fluted resilient plates 3| for the reception of studs 32 carried by suitable brackets-secured to the transverse end members of. the frame IS, in accordance with the showing in the aforementioned patent. r I

Aside from the resilient journal 30, nothing novel is claimed for the foregoing, the same having been previously disclosed.

Considering now the salient feature of the present invention, particular attention is directed to Figure 1, in which a transverse housing 33 is rigidly secured to the side stretches of the screen frame l9 intermediate its ends, said housing being provided with a removable bottom 34, having an opening therein normally closed by an inspection plate 35, bolted and suitably se cured to the bottom 34, and within the housing 33 is a transverse leaf spring 36, provided with downwardly and inturned ends 31 securely fastened to the bottom 34 by the bolts 38, or any other suitable means,

Flat leaf springs 39 are secured to the upper and lower faces of the spring 36 intermediate its ends, and in that form of the invention illusof the housing 33. The'springs 39 serve to distribute the flexing strain throughout the length of the spring 36, while the coil springs 46, which are normally under tension, not only aid in supporting the weight of the striker, but also augment the primary vibration of the spring 36 imparted to the striker. It will be noted that four ,5 coil springs 40 are preferably employed both below and above the spring 36, inasmuch as the same serve to best stabilize the weight of the striker, and are capable of longer life than comparatively stiffer springs, which would be requiredif a fewer number were to be used.

Secured to the top and bottom sides of the spring 36 are the weighted blocks 4! provided with central openings alined with corresponding openings in both the springs 39 and the spring 36. Plates 42'are fastened to the blocks 4| by the bolts 43, which also assemble the blocks 4| and the springs 39 on the spring 36. Shims 44 disposed between the bottom block 4! and the lower plate 42 permit adjustment of the lower plate with relation to the top plate, which provides necessary take-up in the event of wear between the strikerand button .to be described. Hardened discs 45 are secured to the inner faces of the plates 42, theupper plate andthe hardened disc secured thereto having alined openings for the reception of a threaded stud 46, the lower end of which is provided with a head or button 41 disposed between the hardened striker discs 45, as best shown in Figure l. The stud 46 passes through the central vibrating channel 26, and the cooperating clamping strap 21, and is adjustably secured thereto by the upper and lower nuts48. The top of the housing 33, through which the stud 36 passes, isprovided with an opening surrounded byan upturned flange 49, which is sealed in any suitable manner, as for instance by thin, laminated metalrwashers 50 impregnated with asbestos, in lieu of rubber or, other. material affected by heat.

From the foregoing explanation, considered in connection with the accompanying drawings, it is believed that the operation of the invention will be 'quite apparent, in that primary vibratory movement is imparted to the screen S through the overbalanced pulleys l3 mounted above the screen frame, which in turn is journaled in the resilient bearing blocks 1. Vibration of the screen S necessarily imparts vibratory movement to the striker through the spring 36, resulting in a sharp tapping action beingirnparted to the screening medium 20 through'the impact of the striker upon the head or button 4? 'carriedby the 'intermediate channel secured to the screening medium, andfl-particular attention is directed to thefact that the use of a striker,

having two striking surfaces 'foralternate engagement with the striker button, acts as'a controlling and limiting means for the striker, thus preventing the samefrom'attaining suflicient amplitude of vibration to be destructive to the springs employed.

Furthermore, by adjustment of the threaded stud 46, in opposite directions, either the upper or lower striking surfaces may be brought into contact with the button 42', thus permitting impact of the striker to be impartedto the screening medium in either an upward or downward direction, or both, when the button is adjusted to a central position, as shown in Figure 1.

The spring 36 having inwardly curved ends permits the required flexibility, and at the same time is ofsuflicient rigidity to avoid any possible side movement of the striker, as the result of the orbitary vibrating movement of the screen S in a transverse plane to the spring. Therefore, it will be noted that the spring 36 is so constructed as to both stabilize the weight of the striker, and positively control the direction of its movement. A further important function of the spring 36 results from the fact that it augments the primary vibration of the screen S,

and imparts the same to the striker, with the result that the striker is given an amplitude of stroke excessively greater than the primary vibration of the screen S.

In that form of the invention illustrated, use

of the coil springs 46 produce the most practical results. However, in some instances it is unnecessary to utilize the same. Therefore, the invention contemplates a striker, such as described, with or without said springs. For example, one of the important uses of the present invention is in connection with a multiple decked screen, in which the various decks employ screens of difierent mesh. In suchscreens the mesh employed in the top deck is usually larger than that of the lower deck, and therefore requires a relatively long stroke with resultant slow vibratory speed. However, the same stroke and speed are not practical for the smaller mesh, inasmuch as the resulting vibratory action is too sluggish. At the same time, the screen cannot be actuated at high speed with a resultant short stroke, as this would be insuficient to'move the material on the larger mesh.

Therefore, application of the present invention to the smaller mesh screen, in a multiple deck screen operated at relatively low speed and long stroke, compensates for, such action and causes sufficient vibration of the smaller mesh screen to cause the same to eificiently perform its function. However, in the foregoing appli-- cation of the invention it has been found that use of the coil springs 40 are not essential, due to the slow primary vibratory action, and the fact that at slow speeds the spring 36 has sufficient tension to control the vibratory action ofthe striker, it being merely necessary to determine the proper weight' of the striker for a given speed to cause the striker to operate most effectively.

The flexible connection of the vibratory channels 26 to the screen frame I9 is important as regards the distinction over the structure disclosed in Patent No. 2,032,062, in that rubber employed in the earlier structure would quickly deteriorate because of the excessive heat of the material handled, whereas in the present structure the fluted steel plates, formed in two halves to facilitate assembly, offer the desired resiliency and insure long life for the bearing.

We claim:

1. In a vibrating screen including a vibratory frame and a screening medium carried thereby, a striker mechanism carried by said frame and including a leaf spring anchored at its opposite ends, auxiliary springs positioned upon opposite sides of said leaf spring intermediate its ends for affecting its action, a striker carried by said leaf spring intermediate its ends, and adjustable means carried by said screening medium for impact with said striker, said striker and said adjustable means both having two contact surfaces for obtaining impact between said striker and adjustable means either in an upward direction a striker mechanism carried by said frame and including a leaf spring anchored at its opposite ends, a. striker carried by said leaf spring intermediate its ends, and adjustable means carried by said screening medium for impact with said striker, said striker and said adjustable means both having two contact surfaces for obtaining impact between said striker and adjustable'means either in an upward direction or downward direction, or both.

3. A vibrating-screen assembly including a vibratory frame and a single screening medium carried thereby, a striker mechanism carried by and movable with relation to the vibratory frame for actuation by the latter, and means supported by the screening medium for engagement by said striker mechanism during both upward and downward movements of the latter and for limiting said movements of the striker mechanism.

4. A vibrating screen assembly including a vibratory frame and a single screening medium carried thereby, spaced striker members mounted upon and movable with relation to said frame for actuation by the latter, and means connected to said screening medium having a part interposed between the striker members and spaced therefrom for intermittent engagement thereby when said striker members are vibrated in a vertical direction, and to limit the movement of the striker members relative to said screening medium.

5. A vibrating screen assembly including a vibratory frame and a single screening medium carried thereby, spaced striker members mounted upon and movable with relation to said frame for actuation by the latter, and means connected to saidscreening medium having a part interposed between said striker members and spaced therefrom for intermittent engagement by the latter when said striker members are vibrated in a vertical direction by the frame.

6. A vibrating screen assembly including a vibratory frame and a single screening medium carried thereby, resilient -means carried by said frame, spaced striker members supported by the resilient means and actuated by said frame, and a member carried by said screening medium formed to receive impact in upward and downward directions from said striker members during vibratory movement of the frame.

7. A vibrating screen assembly including a vibratory frame and a single screening medium carried thereby, spaced hammers supported on and movable with relation to said frame and actuated by the latter, and a unitary means having a pair of oppositely facing striking surfaces connected to said screening medium and interposed between said hammers for intermittent engagement by the latter when the same are vibrated, whereby to impart a positive two directional movement to said screening medium.

8. A vibrating screen assembly including a vibratory frame and a single screening medium carried thereby, resilient means carried by said frame, spaced hammers mounted on the resilient means and actuated by said frame, and a unitary means having a pair of oppositely facing striking surfaces connected to said screening medium and interposed between said hammers for intermittent engagement by the latter when the same are vibrated, whereby to impart a positive two directional movement to said screening medium.

EMIL E. DEISTER. IRWIN F. DEISTER. 

